Maria Cefola (Institute of Sciences of Food Production, CNR - National Research Council of Italy Via G. Amendola, 122/O – 70126 Bari, Italy) Maria Luisa Amodio and Giancarlo Colelli (Dept. SAFE, University of Foggia, Via Napoli 25, 71122 Foggia, Italy)
Low oxygen controlled atmosphere was reported to be useful for fresh-cut broccoli raab cold storage in maintaining freshness and qualitative traits. Starting from these finding the aim of this work was to evaluate the proper modified atmosphere packaging (MAP) for fresh-cut broccoli raab in order to achieve and maintain low oxygen atmosphere composition during cold storage. Broccoli raabs harvested from a commercial farm, were selected for defects and were cut from the stalks, obtaining the ready-to-use product. After washing the product was packaged in plastic trays sealed in bags of different plastic materials. Two commercially available polymeric coupled films (polypropylene/polyethylene terephthalate, PP/PET, and polypropylene/polyamide, PP/PA microperforated (MF), were used as packaging materials with or without the inclusion of a CO2 absorbers (used in 5-g sachets). For each packaging condition a passive (P-MAP) and an active atmosphere with 5% O2 in nitrogen (A-MAP) were used. Unpackaged samples were used as control and stored with all packages at 5 degree C. Initially, and after 3 and 8 days samples were taken and quality attributes (overall appearance, odour and flavour, colour analysis and weight loss) were evaluated. Gas concentration were also monitored. Among the packaging treatments tested the combination using PP/PA in A-MAP with and the use of CO2 absorbing sachets reached equilibrium condition very close to optimal for broccoli raab. Fresh-cut broccoli raab stored in this condition for 8 days showed the best appearance, odour, and flavour scores, compared to all other packaging combinations.